Enhanced lipid accumulation in Metschnikowia pulcherrima using volatile fatty acids under non-sterile repeated batch cultivation

Thraustochytrids, such as members of the genus Aurantiochytrium, are rich in docosahexaenoic acid (DHA, C22:6n-3) and represent a promising source of omega-3 fatty acids which plays a vital role in the enhancement of human health, particularly for neurological and visual functions. Different modes of cultivation (batch, fed-batch and repeated-batch) by Aurantiochytrium sp. SW1 were studied for effective docosahexaenoic acid (DHA) production. In this study, three different modes of fermentation were carried out in 1 L shake flasks with a working volume of 500 mL, incubated at 30 ºC and 200 rpm. Batch cultivation significantly exceeds the rest of cultivation modes, achieving maximal lipid and DHA concentrations of 11.22 g/L and 5.87 g/L, respectively, and DHA productivity of 0.061 g/L/h. Lipid and DHA concentration of the repeated-batch process decreased through the cycles for all three different types of replacement ratio (80, 90 and 95%). The average decrease percentage of DHA concentration for cycle one and cycle two were 21.76 and 32.52%, respectively. However, the fatty acid composition of lipids obtained in the cycles remained consistent with 16:0 and DHA being the most abundant fatty acids indicating that this mode of fermentation is highly useable for industrial applications.

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Unravelling a microbial synergy to boost caproate production via carboxylates chain elongation with ethanol

HKIE Transactions ◽

10.33430/v26n2thie-2018-0041 ◽

2019 ◽

Vol 26 (2) ◽

pp. 63-71

Author(s):

Ling Leng ◽

Ying Wang ◽

Peixian Yang ◽

Takashi Narihiro ◽

Masaru Konishi Nobu ◽

...

Keyword(s):

Fatty Acids ◽

Volatile Fatty Acids ◽

Microbial Consortia ◽

Chain Elongation ◽

Desulfovibrio Vulgaris ◽

Rrna Gene ◽

Selective Enrichment ◽

Microbial Network ◽

Cost Efficient ◽

Rrna Gene Sequencing

Chain elongation of volatile fatty acids for medium chain fatty acids production (e.g. caproate) is an attractive approach to treat wastewater anaerobically and recover resource simultaneously. Undefined microbial consortia can be tailored to achieve chain elongation process with selective enrichment from anaerobic digestion sludge, which has advantages over pure culture approach for cost-efficient application. Whilst the metabolic pathway of the dominant caproate producer, Clostridium kluyveri, has been annotated, the role of other coexisting abundant microbiomes remained unclear. To this end, an ethanol-acetate fermentation inoculated with fresh digestion sludge at optimal conditions was conducted. Also, physiological study, thermodynamics and 16 S rRNA gene sequencing to elucidate the biological process by linking the system performance and dominant microbiomes were integrated. Results revealed a possible synergistic network in which C. kluyveri and three co-dominant species, Desulfovibrio vulgaris, Fusobacterium varium and Acetoanaerobium sticklandii coexisted. D. vulgaris and A. sticklandii (F. varium) were likely to boost the carboxylates chain elongation by stimulating ethanol oxidation and butyrate production through a syntrophic partnership with hydrogen (H2) serving as an electron messenger. This study unveils a synergistic microbial network to boost caproate production in mixed culture carboxylates chain elongation.

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МЕТАБОЛИТЫ ПРОБИОТИЧЕСКИХ БАКТЕРИЙ ОТВЕЧАЮТ ЗА ЭФФЕКТИВНОСТЬ ДЕЙСТВИЯ ПРОБИОТИКА "ПРОФОРТ®"

10.33845/0033-3239-2019-68-9-10-45-47 ◽

2019 ◽

Keyword(s):

Fatty Acids ◽

Volatile Fatty Acids ◽

Broiler Chicks ◽

Bacillus Sp

МЕЛИКИДИ В.Х., ТЮРИНА Д.Г., СЕЛИВАНОВ Д.Г., НОВИКОВА Н.И. ООО «БИОТРОФ», Санкт-Петербург Аннотация: Приведены данные исследования методом газожидкостной хроматомасс-спектрометрии метаболитов, синтезируемых пробиотическими бактериями, входящими в состав кормовой добавки «Профорт®». Проведен опыт в условиях интенсивного промышленного птицеводства по применению кормовой добавки «Профорт®» (50 тыс. голов бройлеров в группе). Среди метаболитов пробиотических штаммов Enterococcus sp. и Bacillus sp. обнаружены такие полезные вещества, как молочная кислота, уксусная, пропионовая и другие короткоцепочечные (летучие) жирные кислоты, активные пептиды. Результаты зоотехнического опыта показали, что при скармливании бройлерам пробиотика «Профорт®» (500 г/т) живая масса при убое в 40 дней была выше контроля на 6,9%, конверсия корма улучшилась на 3,0%, а европейский индекс продуктивности бройлеров - на 5,69%. Ключевые слова: ПРОБИОТИКИ, МЕТАБОЛИТЫ, ЛЕТУЧИЕ ЖИРНЫЕ КИСЛОТЫ, ЦЫПЛЯТА-БРОЙЛЕРЫ,ПРОДУКТИВНОСТЬ, PROBIOTICS, METABOLITES, VOLATILE FATTY ACIDS, BROILER CHICKS,PRODUCTIVITY

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